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What is a UPS?
UPS stands for Uninterruptible Power Supply. Its purpose is to supply power to certain
critical or important electronic devices whenever main electric power is interrupted.
Depending on the specific design, a UPS contains one or more batteries,
components to clean up the AC power provided by the utility company and a relay to switch
from main utility power to the battery power in the case of a "stand-by" UPS.
Why is a UPS necessary?
Because the electric power provided by your local utility can suddenly be interrupted do
to a black out, thunder storm or some mechanical failure. A UPS can maintain operation of
critical equipment until utility power is restored or until the equipment can be properly
shut down.
What is a typical application for a UPS
The most typical application is to maintain power on a computer so that, should main
electric power be suddenly lost (because of a black out, a thunder storm or some other
reason), recent work can be saved before the computer shuts down. There are other
important applications:
| * digital recording equipment |
| * communication systems such as central telephone
and intercoms |
| * security and building access systems |
| * data network hubs and routers |
| * data network file servers |
| * point of sale cash registers |
NOTE: these devices are not appropriate for
life support equipment.
How do I select the right UPS for my applications?
The right UPS for your application is determined by several factors. To select the right
UPS you will need to know:
1. The power requirement of your equipment load. How much electric current does
your equipment need? This is usually measured in amps (current), watts (power) or
volt-amps (another measure of power).
2. How long does the UPS need to support operation of the equipment in case of
a black-out? This will be UPSs required "run time".
3. How critical is the application? Of course, any application is
important if you are considering a UPS. However, since the most reliable on-line UPS
models are more expensive than the simpler stand-by models it is best to match the
features of the UPS with the value of the application.
The UPS models are described based on their power rating in terms of their volt-amp (VA) rating. Match this with the power requirement of your
application. The run-time of the UPS is stated for full capacity
current draw and one-half capacity. The most critical applications (security or network
communications) should probably be supported by an on-line model.
The less critical applications (cash registers or work stations) are usually matched with
a stand-by device.
What does "VA" mean?
VA stands for "volt-amp" which equals volts x amps. In the United States
standard residential and commercial electric power is 120 volts AC . Current flows to
electric powered equipment at different rates, depending on how much power the equipment
uses. This measure of current is amperes, or "amps". Volt-amps (volts x amps) is
a measure of the power required by equipment. It is also a measure of the capacity of a
UPS.
What is the difference between a Stand-By and
On-line UPS?
A "stand-by" or "off-line" UPS directs main utility power to your
equipment as long as it's available. When the utility power fails they switch to the
battery as a source of temporary power. Liebert PowerSure Series UPSs are
"stand-by" designs. They also condition the AC power before it reaches your
equipment. Other Liebert designs are "on-line". They always pull power from the
battery to operate connected equipment. The utility power is used to keep the battery
charged.
How long will the battery power last in a black
out?
The amount of time the battery power will last (known as "run time") depends on
the relative amount of power being used by equipment connected to the UPS. This is usually
stated as a time if half the UPSs capacity is being used and a time if all the capacity is
being used. For example a XVRT-1000 model has a run time of 10 minutes at half load and 2
minutes at full load. A XPRT-1500 has a run time of 13 minutes at half load and 5 minutes
at full load. Additional batteries can be added to the XPRT series to extend the UPS run
time.
How do I connect a UPS to my equipment?
The UPS designs presented here plug directly into the wall. Your equipment then plugs into
the UPS.
What type of batteries are used?
The batteries are sealed, valve regulated, reduced maintenance, lead acid cells. Some
batteries are user replaceable. Always consult your owners manual before performing any
maintenance.
How do I know if the battery in my UPS is charged?
All models have battery test or status data output capability which can be monitored on
the front of the UPS or remotely by way of a Standard Network Management Protocol (SNMP)
communication connection and Windows based graphical interface software. (Accessory
components are required.)
What is the shelf life of the battery if not being used?
To keep the batteries in best condition it is recommended that the batteries be recharged
every 4 months when being stored. If the batteries are stored for 6 months or more without
being recharged there is a risk that they will not be rechargeable and will need to be
replaced.
How long will the battery last if the UPS is plugged in and utility power is
not interrupted?
The battery charger will maintain a float-charge on the battery whenever utility power is
available so that the battery will have a full charge when needed. Battery condition
should be checked periodically. Typical battery life when being maintained on utility
power is 3 to 5 years.
Can the batteries be changed?
The XVRT and XPRT models are designed to allow the user to replace the battery when
necessary. Consult the operating manual before attempting battery service.
Can additional battery operating time be added?
Additional battery time can be added to the XPRT models.
What is the recharge time of the batteries?
Recharge time is stated as the time to bring a completed depleted battery back to 90% of
its charge capacity, once main AC power is restored. This time is typically about 5 hours
after complete discharge into 100% capacity load. This time will be greater when charging
additional external battery cabinets used with the larger UPS models. Of course, much less
time it required to recharge the battery when it has only been partially discharged. Note:
connected equipment will be operational while the batteries recharge.
Can these devices be used for mobile applications? How rugged are they?
These products are designed and assembled for an industrial market that demands high
quality components and assembly. There are no published recommendations regarding
portability and use in a mobile application. Naturally, we recommend protecting the UPS in
a padded or shock-mount case. In this manner the UPS should be able to withstand normal
static shocks associated with travel.
What service options are available?
Manufacturer's warranty and service is provided by Xtreme Power Conversion. As a
distributor, Juice Goose provides direct technial support and customer service for all UPS
products it sells. For information or assistance contact Juice Goose.
What is the warranty on the UPSs?
The manufacturer’s warranty period is 3 years from the date of manufacture for
all UPS electronics. The warranty period for batteries is 1 year. |